Content downloaded with fetch() API when Content-Encoding: gzip is se…

…t is not decompressed

https://bugs.webkit.org/show_bug.cgi?id=247421
rdar://101935292

Reviewed by Brent Fulgham.

In 195247@main we adopted CFNetwork SPI to opt-out of content encoding sniffing for XMLHttpRequest.
Content encoding sniffing would cause responses with `Content-Encoding: gzip` and
`Content-Type: application/octet-stream` to be treated as `Content-Type: application/gzip` and
`Content-Encoding: identity` on macOS. The user and developer visible behavior is that the gzipped data
is not decompressed.

This brings that change forward to Fetch requests by setting the ContentEncodingSniffingPolicy flag
in the FetchLoader. As an additional step this also renames the ContentEncodingSniffingPolicy flags to
Default and Disable and replaces raw bools representing those flags with the enum itself.

On iOS the flag has no effect since the default behavior is to opt-out of sniffing.

* LayoutTests/platform/mac-wk1/TestExpectations:
    Skip new worker tests since workers are unsupported in WK1.

* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any-expected.txt: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.js: Added.
(string_appeared_here.forEach.contentType.promise_test.async t):
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.serviceworker-expected.txt: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.serviceworker.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.sharedworker-expected.txt: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.sharedworker.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.worker-expected.txt: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.worker.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/resources/foo.octetstream.gz: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/resources/foo.octetstream.gz.headers: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/resources/foo.text.gz: Added.
* LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/resources/foo.text.gz.headers: Added.

* Source/WebCore/Modules/fetch/FetchLoader.cpp:
(WebCore::FetchLoader::start):
* Source/WebCore/loader/ResourceLoader.cpp:
(WebCore::ResourceLoader::start):
* Source/WebCore/loader/ResourceLoader.h:
(WebCore::ResourceLoader::contentEncodingSniffingPolicy const):
(WebCore::ResourceLoader::shouldSniffContentEncoding const): Deleted.
* Source/WebCore/loader/ResourceLoaderOptions.h:
(WebCore::ResourceLoaderOptions::ResourceLoaderOptions):
* Source/WebCore/loader/ThreadableLoader.cpp:
(WebCore::ThreadableLoaderOptions::isolatedCopy const):
* Source/WebCore/platform/network/BlobResourceHandle.cpp:
(WebCore::BlobResourceHandle::BlobResourceHandle):
* Source/WebCore/platform/network/ResourceHandle.cpp:
(WebCore::ResourceHandle::ResourceHandle):
(WebCore::ResourceHandle::create):
(WebCore::ResourceHandle::contentEncodingSniffingPolicy const):
(WebCore::ResourceHandle::shouldContentEncodingSniff const): Deleted.
* Source/WebCore/platform/network/ResourceHandle.h:
* Source/WebCore/platform/network/ResourceHandleInternal.h:
(WebCore::ResourceHandleInternal::ResourceHandleInternal):
* Source/WebCore/platform/network/cf/ResourceHandleCFNet.cpp:
(WebCore::ResourceHandle::createCFURLConnection):
(WebCore::ResourceHandle::start):
(WebCore::ResourceHandle::platformLoadResourceSynchronously):
* Source/WebCore/platform/network/curl/ResourceHandleCurl.cpp:
(WebCore::ResourceHandle::platformLoadResourceSynchronously):
* Source/WebCore/platform/network/mac/ResourceHandleMac.mm:
(WebCore::ResourceHandle::applySniffingPoliciesIfNeeded):
(WebCore::ResourceHandle::createNSURLConnection):
(WebCore::ResourceHandle::start):
(WebCore::ResourceHandle::platformLoadResourceSynchronously):
* Source/WebCore/xml/XMLHttpRequest.cpp:
(WebCore::XMLHttpRequest::createRequest):
* Source/WebKit/NetworkProcess/NetworkLoadParameters.h:
* Source/WebKit/NetworkProcess/ServiceWorker/ServiceWorkerSoftUpdateLoader.cpp:
(WebKit::ServiceWorkerSoftUpdateLoader::loadFromNetwork):
* Source/WebKit/NetworkProcess/cache/NetworkCacheSpeculativeLoad.cpp:
(WebKit::NetworkCache::SpeculativeLoad::SpeculativeLoad):
* Source/WebKit/NetworkProcess/cache/NetworkCacheSpeculativeLoadManager.cpp:
(WebKit::NetworkCache::SpeculativeLoadManager::preconnectForSubresource):
* Source/WebKit/NetworkProcess/cocoa/NetworkDataTaskCocoa.h:
* Source/WebKit/NetworkProcess/cocoa/NetworkDataTaskCocoa.mm:
(WebKit::NetworkDataTaskCocoa::applySniffingPoliciesAndBindRequestToInferfaceIfNeeded):
(WebKit::NetworkDataTaskCocoa::NetworkDataTaskCocoa):
* Source/WebKit/WebProcess/Network/WebLoaderStrategy.cpp:
(WebKit::WebLoaderStrategy::scheduleLoadFromNetworkProcess):
(WebKit::WebLoaderStrategy::loadResourceSynchronously):
* Source/WebKitLegacy/WebCoreSupport/PingHandle.h:

Canonical link: https://commits.webkit.org/256755@main

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any-expected.txt

@@ -0,0 +1,4 @@
+
+PASS fetched gzip data with content type text should be decompressed.
+PASS fetched gzip data with content type octetstream should be decompressed.
+

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.html

@@ -0,0 +1 @@
+<!-- This file is required for WebKit test infrastructure to run the templated test -->

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.js

@@ -0,0 +1,16 @@
+// META: global=window,worker
+
+const expectedDecompressedSize = 10500;
+[
+    "text",
+    "octetstream"
+].forEach(contentType => {
+    promise_test(async t => {
+        let response = await fetch(`resources/foo.${contentType}.gz`);
+        assert_true(response.ok);
+        let arrayBuffer = await response.arrayBuffer()
+        let u8 = new Uint8Array(arrayBuffer);
+        assert_equals(u8.length, expectedDecompressedSize);
+    }, `fetched gzip data with content type ${contentType} should be decompressed.`);
+});
+

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.serviceworker-expected.txt

@@ -0,0 +1,4 @@
+
+PASS fetched gzip data with content type text should be decompressed.
+PASS fetched gzip data with content type octetstream should be decompressed.
+

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.serviceworker.html

@@ -0,0 +1 @@
+<!-- This file is required for WebKit test infrastructure to run the templated test -->

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.sharedworker-expected.txt

@@ -0,0 +1,4 @@
+
+PASS fetched gzip data with content type text should be decompressed.
+PASS fetched gzip data with content type octetstream should be decompressed.
+

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.sharedworker.html

@@ -0,0 +1 @@
+<!-- This file is required for WebKit test infrastructure to run the templated test -->

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.worker-expected.txt

@@ -0,0 +1,4 @@
+
+PASS fetched gzip data with content type text should be decompressed.
+PASS fetched gzip data with content type octetstream should be decompressed.
+

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.worker.html

@@ -0,0 +1 @@
+<!-- This file is required for WebKit test infrastructure to run the templated test -->

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/resources/foo.octetstream.gz.headers

@@ -0,0 +1,2 @@
+Content-type: application/octet-stream
+Content-Encoding: gzip

LayoutTests/imported/w3c/web-platform-tests/fetch/content-encoding/resources/foo.text.gz.headers

@@ -0,0 +1,2 @@
+Content-type: text/plain
+Content-Encoding: gzip

LayoutTests/platform/mac-wk1/TestExpectations

@@ -722,6 +722,9 @@ imported/w3c/web-platform-tests/IndexedDB/reading-autoincrement-indexes.any.shar
 imported/w3c/web-platform-tests/IndexedDB/reading-autoincrement-store-cursors.any.sharedworker.html [ Skip ]
 imported/w3c/web-platform-tests/IndexedDB/reading-autoincrement-store.any.sharedworker.html [ Skip ]
 imported/w3c/web-platform-tests/IndexedDB/storage-buckets.https.any.sharedworker.html [ Skip ]
+imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.serviceworker.html [ Skip ]
+imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.sharedworker.html [ Skip ]
+imported/w3c/web-platform-tests/fetch/content-encoding/gzip-body.any.worker.html [ Skip ]
 
 # WebKitLegacy doesn't support https-based WPT
 webkit.org/b/246719 imported/w3c/web-platform-tests/reporting/generateTestReport-honors-endpoint.https.sub.html [ Failure ]

Source/WebCore/Modules/fetch/FetchLoader.cpp

@@ -95,6 +95,7 @@ void FetchLoader::start(ScriptExecutionContext& context, const FetchRequest& req
     options.dataBufferingPolicy = DataBufferingPolicy::DoNotBufferData;
     options.sameOriginDataURLFlag = SameOriginDataURLFlag::Set;
     options.navigationPreloadIdentifier = request.navigationPreloadIdentifier();
+    options.contentEncodingSniffingPolicy = ContentEncodingSniffingPolicy::Disable;
 
     ResourceRequest fetchRequest = request.resourceRequest();
 

Source/WebCore/loader/ResourceLoader.cpp

@@ -262,7 +262,7 @@ void ResourceLoader::start()
 
     bool isMainFrameNavigation = frame() && frame()->isMainFrame() && options().mode == FetchOptions::Mode::Navigate;
 
-    m_handle = ResourceHandle::create(frameLoader()->networkingContext(), m_request, this, m_defersLoading, m_options.sniffContent == ContentSniffingPolicy::SniffContent, m_options.sniffContentEncoding == ContentEncodingSniffingPolicy::Sniff, WTFMove(sourceOrigin), isMainFrameNavigation);
+    m_handle = ResourceHandle::create(frameLoader()->networkingContext(), m_request, this, m_defersLoading, m_options.sniffContent == ContentSniffingPolicy::SniffContent, m_options.contentEncodingSniffingPolicy, WTFMove(sourceOrigin), isMainFrameNavigation);
 }
 
 void ResourceLoader::setDefersLoading(bool defers)

Source/WebCore/loader/ResourceLoader.h

@@ -130,7 +130,7 @@ class ResourceLoader : public CanMakeWeakPtr<ResourceLoader>, public RefCounted<
     bool shouldSendResourceLoadCallbacks() const { return m_options.sendLoadCallbacks == SendCallbackPolicy::SendCallbacks; }
     void setSendCallbackPolicy(SendCallbackPolicy sendLoadCallbacks) { m_options.sendLoadCallbacks = sendLoadCallbacks; }
     bool shouldSniffContent() const { return m_options.sniffContent == ContentSniffingPolicy::SniffContent; }
-    bool shouldSniffContentEncoding() const { return m_options.sniffContentEncoding == ContentEncodingSniffingPolicy::Sniff; }
+    ContentEncodingSniffingPolicy contentEncodingSniffingPolicy() const { return m_options.contentEncodingSniffingPolicy; }
     WEBCORE_EXPORT bool isAllowedToAskUserForCredentials() const;
     WEBCORE_EXPORT bool shouldIncludeCertificateInfo() const;
 

Source/WebCore/loader/ResourceLoaderOptions.h

@@ -126,11 +126,9 @@ enum class ApplicationCacheMode : uint8_t {
 };
 static constexpr unsigned bitWidthOfApplicationCacheMode = 1;
 
-// FIXME: These options are named poorly. We only implement force disabling content encoding sniffing, not enabling it,
-// and even that only on some platforms.
 enum class ContentEncodingSniffingPolicy : bool {
-    Sniff,
-    DoNotSniff
+    Default,
+    Disable
 };
 static constexpr unsigned bitWidthOfContentEncodingSniffingPolicy = 1;
 
@@ -163,7 +161,7 @@ struct ResourceLoaderOptions : public FetchOptions {
         : FetchOptions { WTFMove(options) }
         , sendLoadCallbacks(SendCallbackPolicy::DoNotSendCallbacks)
         , sniffContent(ContentSniffingPolicy::DoNotSniffContent)
-        , sniffContentEncoding(ContentEncodingSniffingPolicy::Sniff)
+        , contentEncodingSniffingPolicy(ContentEncodingSniffingPolicy::Default)
         , dataBufferingPolicy(DataBufferingPolicy::BufferData)
         , storedCredentialsPolicy(StoredCredentialsPolicy::DoNotUse)
         , securityCheck(SecurityCheckPolicy::DoSecurityCheck)
@@ -184,7 +182,7 @@ struct ResourceLoaderOptions : public FetchOptions {
     ResourceLoaderOptions(SendCallbackPolicy sendLoadCallbacks, ContentSniffingPolicy sniffContent, DataBufferingPolicy dataBufferingPolicy, StoredCredentialsPolicy storedCredentialsPolicy, ClientCredentialPolicy credentialPolicy, FetchOptions::Credentials credentials, SecurityCheckPolicy securityCheck, FetchOptions::Mode mode, CertificateInfoPolicy certificateInfoPolicy, ContentSecurityPolicyImposition contentSecurityPolicyImposition, DefersLoadingPolicy defersLoadingPolicy, CachingPolicy cachingPolicy)
         : sendLoadCallbacks(sendLoadCallbacks)
         , sniffContent(sniffContent)
-        , sniffContentEncoding(ContentEncodingSniffingPolicy::Sniff)
+        , contentEncodingSniffingPolicy(ContentEncodingSniffingPolicy::Default)
         , dataBufferingPolicy(dataBufferingPolicy)
         , storedCredentialsPolicy(storedCredentialsPolicy)
         , securityCheck(securityCheck)
@@ -218,7 +216,7 @@ struct ResourceLoaderOptions : public FetchOptions {
 
     SendCallbackPolicy sendLoadCallbacks : bitWidthOfSendCallbackPolicy;
     ContentSniffingPolicy sniffContent : bitWidthOfContentSniffingPolicy;
-    ContentEncodingSniffingPolicy sniffContentEncoding : bitWidthOfContentEncodingSniffingPolicy;
+    ContentEncodingSniffingPolicy contentEncodingSniffingPolicy : bitWidthOfContentEncodingSniffingPolicy;
     DataBufferingPolicy dataBufferingPolicy : bitWidthOfDataBufferingPolicy;
     StoredCredentialsPolicy storedCredentialsPolicy : bitWidthOfStoredCredentialsPolicy;
     SecurityCheckPolicy securityCheck : bitWidthOfSecurityCheckPolicy;

Source/WebCore/loader/ThreadableLoader.cpp

@@ -83,6 +83,7 @@ ThreadableLoaderOptions ThreadableLoaderOptions::isolatedCopy() const
     // ResourceLoaderOptions
     copy.sendLoadCallbacks = this->sendLoadCallbacks;
     copy.sniffContent = this->sniffContent;
+    copy.contentEncodingSniffingPolicy = this->contentEncodingSniffingPolicy;
     copy.dataBufferingPolicy = this->dataBufferingPolicy;
     copy.storedCredentialsPolicy = this->storedCredentialsPolicy;
     copy.securityCheck = this->securityCheck;

Source/WebCore/platform/network/BlobResourceHandle.cpp

@@ -155,7 +155,7 @@ void BlobResourceHandle::loadResourceSynchronously(BlobData* blobData, const Res
 }
 
 BlobResourceHandle::BlobResourceHandle(BlobData* blobData, const ResourceRequest& request, ResourceHandleClient* client, bool async)
-    : ResourceHandle { nullptr, request, client, false /* defersLoading */, false /* shouldContentSniff */, true /* shouldContentEncodingSniff */, nullptr /* sourceOrigin */, false /* isMainFrameNavigation */ }
+    : ResourceHandle { nullptr, request, client, false /* defersLoading */, false /* shouldContentSniff */, ContentEncodingSniffingPolicy::Default, nullptr /* sourceOrigin */, false /* isMainFrameNavigation */ }
     , m_blobData { blobData }
     , m_async { async }
 {

Source/WebCore/platform/network/ResourceHandle.cpp

@@ -77,8 +77,8 @@ void ResourceHandle::registerBuiltinSynchronousLoader(const AtomString& protocol
     builtinResourceHandleSynchronousLoaderMap().add(protocol, loader);
 }
 
-ResourceHandle::ResourceHandle(NetworkingContext* context, const ResourceRequest& request, ResourceHandleClient* client, bool defersLoading, bool shouldContentSniff, bool shouldContentEncodingSniff, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation)
-    : d(makeUnique<ResourceHandleInternal>(this, context, request, client, defersLoading, shouldContentSniff && shouldContentSniffURL(request.url()), shouldContentEncodingSniff, WTFMove(sourceOrigin), isMainFrameNavigation))
+ResourceHandle::ResourceHandle(NetworkingContext* context, const ResourceRequest& request, ResourceHandleClient* client, bool defersLoading, bool shouldContentSniff, ContentEncodingSniffingPolicy contentEncodingSniffingPolicy, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation)
+    : d(makeUnique<ResourceHandleInternal>(this, context, request, client, defersLoading, shouldContentSniff && shouldContentSniffURL(request.url()), contentEncodingSniffingPolicy, WTFMove(sourceOrigin), isMainFrameNavigation))
 {
     if (!request.url().isValid()) {
         scheduleFailure(InvalidURLFailure);
@@ -91,14 +91,14 @@ ResourceHandle::ResourceHandle(NetworkingContext* context, const ResourceRequest
     }
 }
 
-RefPtr<ResourceHandle> ResourceHandle::create(NetworkingContext* context, const ResourceRequest& request, ResourceHandleClient* client, bool defersLoading, bool shouldContentSniff, bool shouldContentEncodingSniff, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation)
+RefPtr<ResourceHandle> ResourceHandle::create(NetworkingContext* context, const ResourceRequest& request, ResourceHandleClient* client, bool defersLoading, bool shouldContentSniff, ContentEncodingSniffingPolicy contentEncodingSniffingPolicy, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation)
 {
     if (auto protocol = request.url().protocol().toExistingAtomString(); !protocol.isNull()) {
         if (auto constructor = builtinResourceHandleConstructorMap().get(protocol))
             return constructor(request, client);
     }
 
-    auto newHandle = adoptRef(*new ResourceHandle(context, request, client, defersLoading, shouldContentSniff, shouldContentEncodingSniff, WTFMove(sourceOrigin), isMainFrameNavigation));
+    auto newHandle = adoptRef(*new ResourceHandle(context, request, client, defersLoading, shouldContentSniff, contentEncodingSniffingPolicy, WTFMove(sourceOrigin), isMainFrameNavigation));
 
     if (newHandle->d->m_scheduledFailureType != NoFailure)
         return newHandle;
@@ -270,9 +270,9 @@ bool ResourceHandle::shouldContentSniff() const
     return d->m_shouldContentSniff;
 }
 
-bool ResourceHandle::shouldContentEncodingSniff() const
+ContentEncodingSniffingPolicy ResourceHandle::contentEncodingSniffingPolicy() const
 {
-    return d->m_shouldContentEncodingSniff;
+    return d->m_contentEncodingSniffingPolicy;
 }
 
 bool ResourceHandle::shouldContentSniffURL(const URL& url)

Source/WebCore/platform/network/ResourceHandle.h

@@ -26,6 +26,7 @@
 #pragma once
 
 #include "AuthenticationClient.h"
+#include "ResourceLoaderOptions.h"
 #include "StoredCredentialsPolicy.h"
 #include <wtf/Box.h>
 #include <wtf/MonotonicTime.h>
@@ -95,7 +96,7 @@ class CurlResourceHandleDelegate;
 
 class ResourceHandle : public RefCounted<ResourceHandle>, public AuthenticationClient {
 public:
-    WEBCORE_EXPORT static RefPtr<ResourceHandle> create(NetworkingContext*, const ResourceRequest&, ResourceHandleClient*, bool defersLoading, bool shouldContentSniff, bool shouldContentEncodingSniff, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation);
+    WEBCORE_EXPORT static RefPtr<ResourceHandle> create(NetworkingContext*, const ResourceRequest&, ResourceHandleClient*, bool defersLoading, bool shouldContentSniff, ContentEncodingSniffingPolicy, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation);
     WEBCORE_EXPORT static void loadResourceSynchronously(NetworkingContext*, const ResourceRequest&, StoredCredentialsPolicy, SecurityOrigin*, ResourceError&, ResourceResponse&, Vector<uint8_t>& data);
     WEBCORE_EXPORT virtual ~ResourceHandle();
 
@@ -150,7 +151,7 @@ class ResourceHandle : public RefCounted<ResourceHandle>, public AuthenticationC
     bool shouldContentSniff() const;
     static bool shouldContentSniffURL(const URL&);
 
-    bool shouldContentEncodingSniff() const;
+    ContentEncodingSniffingPolicy contentEncodingSniffingPolicy() const;
 
     WEBCORE_EXPORT static void forceContentSniffing();
 
@@ -209,7 +210,7 @@ class ResourceHandle : public RefCounted<ResourceHandle>, public AuthenticationC
     static void registerBuiltinSynchronousLoader(const AtomString& protocol, BuiltinSynchronousLoader);
 
 protected:
-    ResourceHandle(NetworkingContext*, const ResourceRequest&, ResourceHandleClient*, bool defersLoading, bool shouldContentSniff, bool shouldContentEncodingSniff, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation);
+    ResourceHandle(NetworkingContext*, const ResourceRequest&, ResourceHandleClient*, bool defersLoading, bool shouldContentSniff, ContentEncodingSniffingPolicy, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation);
 
 private:
     enum FailureType {
@@ -235,19 +236,19 @@ class ResourceHandle : public RefCounted<ResourceHandle>, public AuthenticationC
 #endif
 
 #if USE(CFURLCONNECTION)
-    void createCFURLConnection(bool shouldUseCredentialStorage, bool shouldContentSniff, bool shouldContentEncodingSniff, RefPtr<SynchronousLoaderMessageQueue>&&, CFDictionaryRef clientProperties);
+    void createCFURLConnection(bool shouldUseCredentialStorage, bool shouldContentSniff, ContentEncodingSniffingPolicy, RefPtr<SynchronousLoaderMessageQueue>&&, CFDictionaryRef clientProperties);
 #endif
 
 #if PLATFORM(MAC)
-    void createNSURLConnection(id delegate, bool shouldUseCredentialStorage, bool shouldContentSniff, bool shouldContentEncodingSniff, SchedulingBehavior);
+    void createNSURLConnection(id delegate, bool shouldUseCredentialStorage, bool shouldContentSniff, ContentEncodingSniffingPolicy, SchedulingBehavior);
 #endif
 
 #if PLATFORM(IOS_FAMILY)
-    void createNSURLConnection(id delegate, bool shouldUseCredentialStorage, bool shouldContentSniff, bool shouldContentEncodingSniff, SchedulingBehavior, NSDictionary *connectionProperties);
+    void createNSURLConnection(id delegate, bool shouldUseCredentialStorage, bool shouldContentSniff, ContentEncodingSniffingPolicy, SchedulingBehavior, NSDictionary *connectionProperties);
 #endif
 
 #if PLATFORM(COCOA)
-    NSURLRequest *applySniffingPoliciesIfNeeded(NSURLRequest *, bool shouldContentSniff, bool shouldContentEncodingSniff);
+    NSURLRequest *applySniffingPoliciesIfNeeded(NSURLRequest *, bool shouldContentSniff, ContentEncodingSniffingPolicy);
 #endif
 
 #if USE(CURL)

Source/WebCore/platform/network/ResourceHandleInternal.h

@@ -65,15 +65,15 @@ class ResourceHandleInternal {
     WTF_MAKE_NONCOPYABLE(ResourceHandleInternal);
     WTF_MAKE_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(ResourceHandleInternal);
 public:
-    ResourceHandleInternal(ResourceHandle* loader, NetworkingContext* context, const ResourceRequest& request, ResourceHandleClient* client, bool defersLoading, bool shouldContentSniff, bool shouldContentEncodingSniff, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation)
+    ResourceHandleInternal(ResourceHandle* loader, NetworkingContext* context, const ResourceRequest& request, ResourceHandleClient* client, bool defersLoading, bool shouldContentSniff, ContentEncodingSniffingPolicy contentEncodingSniffingPolicy, RefPtr<SecurityOrigin>&& sourceOrigin, bool isMainFrameNavigation)
         : m_context(context)
         , m_client(client)
         , m_firstRequest(request)
         , m_lastHTTPMethod(request.httpMethod())
         , m_partition(request.cachePartition())
         , m_defersLoading(defersLoading)
         , m_shouldContentSniff(shouldContentSniff)
-        , m_shouldContentEncodingSniff(shouldContentEncodingSniff)
+        , m_contentEncodingSniffingPolicy(contentEncodingSniffingPolicy)
 #if USE(CFURLCONNECTION)
         , m_currentRequest(request)
 #endif
@@ -107,7 +107,7 @@ class ResourceHandleInternal {
 
     bool m_defersLoading;
     bool m_shouldContentSniff;
-    bool m_shouldContentEncodingSniff;
+    ContentEncodingSniffingPolicy m_contentEncodingSniffingPolicy;
 #if USE(CFURLCONNECTION)
     RetainPtr<CFURLConnectionRef> m_connection;
     ResourceRequest m_currentRequest;